1. Ferrous & Non-ferrous metals:
When metals occur naturally they are called ore and are normally mixed with other metal ores (alloying) to give the desired properties and qualities. Metals are divided into 3 groups;
Ferrous Non-ferrous Alloys
Metal must be extracted from their ore before they can be used; this is done through extraction from the earths core, mining, removal of rocks and other compounds and then reduction which removes oxygen by heating and changes chemical bonding.

2. Ferrous metals:
Production of iron:

3. The Blast Furnace Process
1.   The Iron Ore, Coke and Limestone, (the Charge), is conveyed to the top of the Furnace. 2.   The Charge is stored in Bells until the timing is right for the charge to be dropped into the Furnace. 3.   Hot air is then blown through pipes called Tuyeres, to fire the mixture. 4.   The Coke burns to increase the temperature in the Furnace. 5.   The Limestone attracts the impurities in the Iron Ore and forms Slag. This Slag is lighter than the molten Iron and so floats on top of it. 6.   As the Furnace fills, the molten Iron is Tapped off. The Slag is also tapped off at regular intervals. Most Iron is taken straight from the Blast Furnace to the Steel Mill, but some is poured into buckets called Pigs. This Iron is called Pig Iron and is used to make Cast Iron.

4. Iron Ore
The Iron Ore is first mined and then brought to the Blast Furnace. It contains impurities which have to be removed. Haematite (Hematite) and Magnetite are the most common ores. It takes about two tons of Iron Ore to produce one ton of iron, but this varies with different types of ores.
Coke
Coke is made by heating soft coal in the absence of air. As Coke is burned in the Blast Furnace it raises the temperature to about 2000°C which is enough to melt the Iron Ore. The Carbon in the Coke chemically reacts with the Oxygen in the Iron Ore to form Carbon Dioxide(CO2, and Carbon Monoxide(CO), which escapes through the Gas Outlet.
Limestone
The Limestone is mined then crushed before being brought to the Blast Furnace. It combines with the impurities in the Iron Ore to form Slag. A material which removes unwanted materials or cleans another material is called a Flux. It also acts as a catalyst.

5. Production of Steel:
The process for making steel is called the basic oxygen steel-making process or BOS process.
Oxygen gas is blown through the oxygen lance at high pressure, this reacts with impurities such as carbon and sulphur and oxidises them. These leave as gas (carbon dioxide and sulphur dioxide) and pure iron remains.
Calculated amounts of carbon or other metals are added to make a range of different alloys such as steel.

6. Alloys of steel
Description
Carbon Steel
The most common type of steel with 0.1 to 1% carbon depending on the strength. An important use of this steel is providing the skeleton of large buildings like bridges, airports and skyscrapers.
Stainless Steel
Contains about 18% chromium (Cr) and small amounts of nickel (Ni). It is used for making cutlery because it is resistant to corrosion. It has also been used in a lot of famous skyscraper exteriors.
Titanium Steel
Contains % titanium and various amounts of other metals it is very hard and used in aircraft and armour plating.

7. The molten metal can either be;
Poured directly into an ingot for shipping or use later.
Poured directly into a cast.
Or onto a continuous casting machine.
Continuous casting is the most efficient way of using the metal as it is already molten and will not have to be reheated to form sheet.

8. Continuous casting:
Continuous Casting is the process whereby molten steel is solidified into a "semi finished" billet, bloom, or slab for subsequent rolling in the finishing mills. Prior to the introduction of Continuous Casting in the 1950s, steel was poured into stationary moulds to form "ingots". Since then, "continuous casting" has evolved to achieve improved yield, quality, productivity and cost efficiency.

9. Non-Ferrous metals:
Aluminium: Commercially available in the form of bauxite it is difficult to break down and therefore electrolysis is needed rather than melting so that it can be processed (this process requires a great deal of electrical expenditure).
1.The bauxite (red-brown solid) - aluminium oxide mixed with impurities - is extracted from the earth.
2.The extracted aluminium oxide is then treated with alkali, to remove the impurities. This results in a white solid called aluminium oxide or alumina.
3.The alumina is then transported to huge tanks. The tanks are lined with graphite, this acts as the cathode. Also blocks of graphite hang in the middle of the tank, and acts as anodes.

10. 4.The alumina is then dissolved in molten cryolite - this lowers the melting point - saves money!
5.Electricity is passed and electrolysis begins. Electrolysis is the decomposition of a compound using electricity.
6.When dissolved, the aluminium ions and oxide ions in the alumina can move the aluminium is then tapped off.

12. Micro-structure of metals:
Metals usually have one or two loose electrons in their outer electron shell and therefore they are likely to become easily detached, it is this movement of electrons which accounts for metals high electrical and thermal conductivity. This ability for movement also leads metals to have ductile and malleable properties.
All metals are solid at room temperature; with the exception of mercury. The addition of heat to metals breaks some internal bonds meaning they are only held together by weak forces of attraction. For this reason molten metal can flow.

13. Closed-packed hexagonal (CPH) Face-centred cubic (FCC)
When in a solid state the atoms energy is reduced and they arrange themselves in a regular lattice structure in the form of small seed crystals or grains, there are 3 possible lattice structures;
Closed-packed hexagonal (CPH)
Face-centred cubic (FCC)
Body-centred cubic (BCC)
BCC
CPH
FCC

14. Micro-structure of iron:
Properties
Examples
CPH
Weak, poor strength to weight ratio.
Zinc, magnesium
FCC
Ductile, good electrical conductor.
Gold, copper, silver, aluminium
BCC
Hard, tough.
Chromium, tungsten.
Micro-structure of iron:
Iron changes from BCC lattice to FCC lattice at 9100C and above 14000C it changes back again. In the FCC form it absorbs carbon which essential for steel making.

15. Questions: Explain what is meant by the term alloy?
Explain in detail the difference between ferrous and non-ferrous metals.
Define the terms ductile, malleable and corrosion resistant.
Suggest a use for: Mild Steel, stainless steel,
Aluminium, Copper, Brass &
Lead

18. The hardening of metal:
Heat treatment is the process of heating and cooling metals in a controlled way, in order to change their properties and characteristics.
The various heating processes fall into the following categories:
Hardening processes - These processes are intended to produce a hardened structure. Hardening increases wear resistance and material strength, but often makes the structure of the metal brittle.
Softening processes - These processes are intended primarily to soften the material, or remove stresses built up as the metal is worked.
Toughening processes - These processes are intended to produce a structure which improves strength and ductility.
Case-hardening process - These processes are employed to produce a 'case' or surface layer which is harder than the interior core of the metal.

19. The only method of hardening most metals (other than some steels) is by work hardening. Work hardening takes place when a metal has been deformed (by hammering, bending, pressing or rolling for instance). The internal stresses that are set up as a material is worked have to be relieved by a process called annealing (this is the addition of heat at a low temperature).
Task- Copy table from p196 “Heat treatment processes).
Question: Explain why case hardening and induction hardening are vital to the production of a car?